A possible participation of endogenous opiates in respiratory reflexes induced by thin-fiber muscular afferents

doi:10.1016/0006-8993(80)90248-6

Brain Research

Volume 199, Issue 1, 13 October 1980, Pages 244-248

https://doi.org/10.1016/0006-8993(80)90248-6 Get rights and content

Summary

In anesthetized, vagotomized, paralyzed, and artificially ventilated dogs, naloxone effects on respiratory responses induced by thin-fiber muscular afferents were studied by recording phrenic nerve discharges.

Naloxone augmented respiratory outputs, before, during, and after the stimulation.

Two different types were found in the returning phase of the respiratory response by thin-fiber muscular afferent stimulation: respiratory outputs were supressed below the pre-stimulus level within several minutes after the cessation of the stimulus in some cases, while in the other cases they remained above the pre-stimulus level. In the latter cases, naloxone did not change the pattern of returning phase of the response, on the other hand, in the former cases, the after-suppression was significantly reduced by naloxone.

The present results suggest that endogenous opiates play a role in setting the level of respiratory outputs and that in addition to facilitatory effects on respiration, thin-fiber muscular afferents drive a negative feedback system via neurohumoral mechanisms.

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A possible participation of endogenous opiates in respiratory reflexes induced by thin-fiber muscular afferents

Summary

Brain Research

Brain Research

Brain Research

Brain Research

Life Sci.

Life Sci.

Peripheral afferent pathway for acupuncture analgesia

Scientia Sinica

Central neural respiratory stimulatory effect of active respiration

J. appl. Physiol.